1. Field of the Invention
The present invention relates to a photographing optical lens assembly, and more particularly, to a photographing optical lens assembly with reduced optical sensitivity and high resolution.
2. Description of the Prior Art
A conventional high resolution compact photographing optical lens assembly is generally configured such that a frontal aperture stop is adopted and there are four lens elements in the assembly, wherein the first lens element and the second lens element with spherical surfaces made of glass are usually combined together into a doublet lens structure in order to correct chromatic aberrations. This is disclosed in U.S. Pat. No. 7,365,920 and there are drawbacks with this method. First, an arrangement of too many spherical lenses will limit the freedom in optical system design, which makes it difficult to shorten the total track length of the system. Secondly, the bonding of glass lenses is difficult in manufacturing process. A lens assembly with four independent lenses is disclosed in U.S. Pat. No. 7,277,238, including multiple aspheric lenses which effectively shorten the total track length of the system and obtaining good image quality. However, due to the aperture stop of the system is positioned in front of the first lens element, the system sensitivity is increased which also increases the difficulty in controlling the yields in manufacturing.